WASHINGTON: Defending champion Ivo Karlovic squandered a match point and 30 aces in losing to Germany's 131st-ranked Peter Gojowczyk in three tie-breaker sets Thursday at the ATP Hall of Fame Open.
Gojowczyk fired 12 aces of his own and saved one break point in each set of his 7-6 (7/5), 6-7 (1/7), 7-6 (7/4) triumph over two hours and 26 minutes at the Newport, Rhode Island, grasscourt event.
The 28-year-old from Munich booked a Saturday semi-final date against 249th-ranked Australian qualifier Matthew Ebden, who rallied to oust Germany's Tobias Kamke 4-6, 7-6 (8/6), 6-4.
Each semi-finalist seeks his first ATP singles title.
Karlovic, ranked 25th, had sought a ninth career ATP crown and had a match point with a break chance as Gojowczyk served at 4-5 in the third set, but the 38-year-old Croatian second seed could not convert.
Karlovic pulled level at 4-4 in the tiebreaker but dropped the next point on his serve and the German took the final two points on his serve to dethrone the champion, who finally won last year after 2014 and 2015 Newport finals defeats.
Karlovic also lost his only prior match with Gojowczyk at Beijing in 2014.
Ebden, who won his only prior match against Kamke in the first round of the 2014 US Open, needed two hours and 41 minutes to subdue his 185th-ranked rival at Newport.
Friday's final quarter-final matches send US top seed John Isner against compatriot Dennis Novikov and American Bjorn Fratangelo against French fourth seed Pierre-Hugues Herbert.